This invention generally relates to the art of electrical connectors and, particularly, to an electrical connector for mounting on a surface of a printed circuit board and includes a terminal tail aligning device.
A known type of input/output (I/O) electrical connector includes an elongated dielectric housing having a front mating face and a rear face with a plurality of terminal-receiving passages extending therebetween. The faces extend longitudinally between opposite ends of the elongated housing. A plurality of terminals are received in the passages. Each terminal includes a forwardly projecting contact portion and a tail portion projecting rearwardly from the housing beyond the rear face thereof.
Electrical connectors of the character described above often include terminal tail aligning devices. This is particularly true wherein the terminals of the connectors are connected to appropriate circuit traces on a printed circuit board. With the ever-increasing miniaturization and density of electronic circuitry, the tail portions of the terminals tend to be very thin and, therefore, fragile. As a result, it is advantageous to support the tail portions so that they will be properly aligned with plated holes in the printed circuit board. Specifically, the tail aligning devices are mountable on the connector housing and even may be movably mounted thereon. The tail aligning devices have a plurality of apertures through which the tail portions of the terminals extend to maintain the tail portions in proper position and spacing.
One of the problems with connectors of the character described above is that the connector housing often becomes rather thick to provide proper retention for the fragile terminals. It has been found with the invention that a tail aligning device can be fixed to the housing and spaced from the rear face thereof to not only align the terminal tail portions but to allow the housing to be made thinner. Thick plastic housings tend to create irregular shrinkage problems when cured. Long terminal-receiving passages in thick housings are difficult to mold, and it is difficult to insert the terminals into long passages.
Another problem associated with such connectors is when the connectors and, particularly, the tail portions of the terminals are surface-mounted on the printed circuit board rather than inserted into holes in the board. Surface mount terminal tails include bent or angled xe2x80x9cfeetxe2x80x9d portions for solder-connection to flat pads on the circuit board. When the feet are bent or formed at an angle to the tail portions, the tail portions may bow unnecessarily and can even become deformed. It has been found by the invention that a properly positioned tail aligning device can also aid in preventing unnecessary bowing of the terminal tails during formation of the surface mounting feet thereof.
The present invention is directed to providing a tail aligning device which helps solve the various problems outlined above.
An object, therefore, of the invention is to provide a new and improved electrical connector for mounting on a surface of a printed circuit board and which includes a tail aligning device.
In the exemplary embodiment of the invention, the connector includes an elongated dielectric housing having a central body portion with a front mating face, a lower face and a plurality of terminal-receiving passages extending therebetween. A plurality of terminals are received in the passages. Each terminal includes a forward contact portion and a tail portion projecting from the body portion beyond the lower face thereof. The tail portions include right-angled end portions or xe2x80x9cfeetxe2x80x9d for surface mounting on the printed circuit board. An elongated tail aligner is fixed to the housing spaced from the lower face thereof. The tail aligner has a plurality of apertures through which the tail portions of the terminals extend.
As disclosed herein, the elongated tail aligner is located on the tail portions of the terminals spaced from the right-angled end portions thereof. The tail aligner is spaced from the lower face of the housing a distance at least equal to a thickness of the tail aligner. Two rows of the terminals have tail portions extending through a corresponding pair of rows of apertures in the tail aligner.
According to further aspects of the invention, the connector housing includes a pair of board mounting portions at opposite ends of the body portion and between which the tail aligner extends. The board mounting portions project past the lower face of the body portion. Each board mounting portion includes a board mounting face generally flush with the right-angled end portions of the terminals and an inside face to which one end of the elongated tail aligner is fixed. The tail aligner is fixed in recesses in the inside faces of the board mounting portions of the housing.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.